The only exp that I have with Nicad batteries is in aircraft. 1. They are very expensive compared to lead-acid. Almost double. 2. They take a lot of maintenance. My company removes them every 300 hours and sends them to the battery shop. 3. The only beauty of a NiCad is that it will give up to 95% of it's capacity at the rated voltage and then it will die. 4. Nicads will develop a 'Memory'. If you discharge and charge it the same amount day after day it will not deliver it's full capacity much beyond what you are normally do on the daily basis. You will have to 'Deep cycle' the battery to regain the rated capacity. 5. NiCad can 'Run away' during the charging phase. They have to be monitored for amperage and internal temp during the charge cycle. Failure to do this may result in the battery exploding. (worst case) The only purpose for Nicads in aviation is their ability to start jet engines. Turbine engines use an incredible amount of amperage during the start cycle. Be that as it may, most operators are going back to Lead-acid just to get away from the maint costs. Morley > Nicad batteies are extremely expensive in the > capacities we need for cruising boats' house banks. > It's true, they need practically no maintenence,

> > 3. The only beauty of a NiCad is that it will give up to 95% of it's > capacity at the rated voltage and then it will die. > > The only purpose for Nicads in aviation is their ability to start jet > engines. Is it not also the case tha nicads have a superior energy/weight ratio and thus they save weight? Hal